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Equipment Held for Operating Lease and Notes Receivable - Narrative (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2022 USD ($)	Mar. 31, 2021 USD ($)	Mar. 31, 2022 engine	Mar. 31, 2022 aircraft.	Mar. 31, 2022 marineVessel	Dec. 31, 2021 USD ($)	Dec. 31, 2021 engine	Dec. 31, 2021 aircraft.	Dec. 31, 2021 marineVessel
Lessor, Lease, Description [Line Items]
Notes receivable	$ 114,253					$ 115,456
Number of leased assets			298	12	1		304	12	1
Note Receivable
Lessor, Lease, Description [Line Items]
Interest income	$ 2,100	$ 2,900
Minimum \| Note Receivable
Lessor, Lease, Description [Line Items]
Note receivable, effective interest rate	6.30%	6.30%
Maximum \| Note Receivable
Lessor, Lease, Description [Line Items]
Note receivable, effective interest rate	12.20%	13.70%
Equipment Held For Operating Lease
Lessor, Lease, Description [Line Items]
Equipment held for operating lease, property, equipment, and furnishings, less accumulated depreciation	$ 1,951,448					$ 1,991,368